


Succubus of the Sea

by AstraeasGalaxy



Category: Ensemble Stars! (Video Game)
Genre: Alternate Universe, Alternate Universe - Fantasy, F/M, M/M, siren au
Language: English
Status: In-Progress
Published: 2020-05-28
Updated: 2020-08-10
Packaged: 2021-03-02 18:14:00
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 8,955
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24421114
Author URL: https://archiveofourown.org/users/AstraeasGalaxy/pseuds/AstraeasGalaxy
Summary: Temptation is a powerful thing, isn't it?
Relationships: Morisawa Chiaki/Narukami Arashi, Nagumo Tetora/Sengoku Shinobu, Shinkai Kanata/Takamine Midori
Comments: 2
Kudos: 18





	1. Captured Siren

**Author's Note:**

> Hi guys. This was supposed to be a one-shot but it grew into a multi-chapter fic... EDIT: 06/05/2020
> 
> \- Just saying now that everyone calls each other by their first names here.  
> \- The sirens depicted will have mostly flat chests, and their genitals are not important/will not be depicted. Arashi will still be referred to as a female siren.  
> \- I'm not too familiar with the rest of Knights so if they seem off, I'm sorry I'll try my best not to mess their characters up.  
> \- Will add more tags as more chapters are added because I really don't know how this will end anymore.

There were tales that passed down for generations about mythical beings called sirens luring men to their deaths at the Siren's Pass. It was a dangerous but quick path for trading. Many kids who lived on Ryusei Island like to try to sail near Siren's Pass as a stupid teenager challenge, but most of them only ever get to the mouth before backing out. Chiaki was one of those idiots, but it was a more heroic gesture than braggadocio on his part. He was determined to find and save the sailors lost to the Siren's Pass.

As he got older, the myth became nothing more to him than a mere fantasy, told by the elders of the island to scare children not to stray into the pass. There was a small part of him that still believed in the sirens that he has read so much about growing up. As a child, Chiaki wanted to see a siren with his own eyes. The grown up part is conflicting with him internally, trying to rationalize the existence of these creatures.

"Chiaki!" A distant voice called out to him. It was his longtime friend Kanata. "Let's head back home. The sun's going down."

Bookmarking his spot in the book, Chiaki got up to greet his best friend. He dusted the sand off his pants with one hand, his other hand cradling the novel close to his chest. Ryusei Island was fairly small, with only three or four towns on the island. There was one part of the island that wasn't occupied that Chiaki and his friends often visited to avoid the town noise and people.

"What are you reading?" Kanata asked.

"Another book about sirens," Chiaki answered, giving the book a pat. "Apparently some people believe they could be mermaids and mermen, but they're originally bird people. I'm not sure how they came to that conclusion."

Kanata nodded, walking along the shoreline happily like he always did. "Mermaids are their own species, right? Sounds kind of like a nice life, living in the ocean…"

Chiaki shrugged. "If that's what makes you happy, Kanata."

Kanata was known as the resident oddball. No one really talked to him aside from exchanging pleasantries. He didn't have many friends to begin with, so Chiaki reached out to him. He turned out to be a fun, caring guy. His gentleness was enough to infatuate Midori, another friend of theirs.

Now that Chiaki thought about it, most of his friends are a bit strange. Shinobu and Midori were also introverted, they kept to themselves most of the time. Tetora was the one most similar to Chiaki. Though he does not see it, Tetora was as bright as Chiaki in terms of personality. They are both natural leaders though Tetora can't see that yet. Still, Chiaki couldn't ask for a better group of friends. Altogether, they made a pretty great team.

Shinobu and Tetora were splashing away in the water. Shinobu convinced Tetora to play some sort of ninja game with him. It ended with Tetora playfully tackling Shinobu into the water.

When Chiaki and Kanata began to walk back to the town, the two playing in the water took notice. Kanata waved at them to signal it was time to head home for dinner.

"Are you still reading about those sirens? There hasn't been any recent cases of missing sailors, so why bother?" Tetora asked Chiaki.

Chiaki shrugged. "I'm just curious."

"Maybe we will meet one and become friends." Kanata giggled.

Shinobu shrank in fear of the idea. "Friends? With those monsters? Doesn't that sound scary?"

"Or we can become true heroes of this island and take them down before they take any more of our innocent citizens." Chiaki boasted followed by loud laughter. No one dared to even think about trying to kill a siren. Their hypnotic voices lulled humans into a sense of security, almost like a demon…or so Chiaki assumed based on all the ghost novels he read. There was a fire burning inside of him that drove him to want to vanquish the monsters once and for all to put the legends to rest. He will then be hailed the hero of Ryusei Island and everyone will live happily ever after.

"There he goes with his heroic speech again." Tetora sighed heavily, shaking his head.

In the distance ahead, a figure was running toward them. It was Midori. Chiaki was so lost in his book he had forgotten Midori was with them when they first got to the quiet part of their island.

"Hey, guys. You may want to hurry back into town," Midori's soft voice called out to them several yards away. He was panting heavily, worn out from running. It looked as if he just came back from the town.

"Midori!" Kanata chimed happily, running to meet up with him. He grabbed both of Midori's hands, spinning himself around, which only dragged Midori to a spin as well. Chiaki was almost jealous of their relationship and how happy they were whenever they saw each other.

"What was that about going back to town?" Chiaki asked curiously.

When Kanata was done spinning him around, Midori's smile went back to its resting position. "One of the old fishermen found and captured a siren. He's bringing it in right now."

Upon hearing the news, Chiaki nearly bolted toward the town. He could hear Kanata in the background shouting his name. He ignored his friends' calls, making a beeline toward the docks. There was a large crowd gathering near one of the boats. The adrenaline in Chiaki's body boosted his speed as he made his way toward the crowd. Slowing down as to not push anyone out of the way, Chiaki gently made his way through the hoard of people to get to the front.

Several men were struggling with a fishing net, with a large body wriggling around in it. Two men grabbed at what appeared to be two brilliant red-colored winged arms that matched its hair. Instead of fingers, there were three talons clawing at the air. It was essentially a naked human with wings and talons. Two other men held both its feathered legs still. Chiaki could see the monster for what it truly was. What tugged at his heart however, was the fear in the siren's vibrant purple eyes, the duct tape over its mouth and now the rope secured around what looked like its wrists. He could see its chest gasping desperately for air as it began to panic. It looked like a child.

"We finally got one! Told ya it was real!" One fisherman boasted loudly. "Should we kill it now?"

"No!" Chiaki shouted above the crowd's noise. Everyone went silent, turning to face him. He gulped at the sudden attention. "I mean…maybe we should keep it alive. Don't you know it's bad luck to kill a siren?"

He was lying, but he hoped it worked to save the young siren. Chiaki was one of the few avid readers in town. Only two other avid readers he knew read any books about sirens all the way through. Hopefully they don't call out his bluff.

"He's right, you know?" The local gossip nodded along. It was tedious to deal with her when she acted like she knew everything first, but this time it helped Chiaki with his bluff.

The fisherman who caught the siren spoke up. "Let's just keep 'em in a cage for now. We could probably sell it for a nice price. We'll discuss this tomorrow when the sun's up."

That wasn't the conclusion Chiaki wanted. It'll have to do for now. The crowd moved about again, with several men bringing a large cage they had saved for diving with sharks. The men holding the siren down tossed the siren in carelessly, immediately closing the cage before it escaped.

Growing up being told that sirens are monsters that needed to be vanquished suddenly felt like a childhood lesson crumbling from adult lies. These sirens allegedly stole the lives of all those sailors that went missing in the Siren's Pass. Chiaki should have seen it as just a monster and allowed the other residents to kill it or sell it without feeling any remorse. Instead, he felt guilty. The siren looked like a child. It had big, fearful eyes as it tried to figure out how to escape its iron prison. When it finally gave in and laid helplessly on the iron floor, Chiaki could see the tears welling up in its eyes.

His friends had already caught up to him by now as he continued to stare at the fragile looking siren. They stared at it as well.

"He looks so scared." Kanata muttered. "Sad…poor little bird."

"I know it probably killed a lot of our sailors, so why do I feel bad looking at it like this?" Midori added. He sighed, most likely thinking how troublesome his thoughts were.

"Where's the siren?" Tetora's voice came from afar, his panting getting louder as he approached them with Shinobu being dragged along with him. Shinobu seemed worn out, but was surprised to see the creature in the cage. Tetora caught a few heavy breaths before looking at it as well. The siren stared back at them, cowering in the back of its cage. The sight wasn't as impressive as Tetora thought it'd be.

"That's it? It looks harmless." Shinobu pouted sadly. "And it looks…helpless."

One of the elders was listening in on their conversation, deciding to butt in. "What are you saying? Just because it looks like a child doesn't mean it's not a monster. These things killed our sailors. If anything, we're severing the lineage so there are no more of these wretched creatures."

"It's time for dinner. Let's go home." Midori spoke up. Kanata nodded, taking one last look at the siren before leaving with Midori. Tetora's stomach growled, which caused him to head home. The crowd was still gathered around the siren, poking and prodding at it.

Seeing a helpless creature give in to whatever the humans were doing to it made Chiaki feel upset. Thankfully no one was hurting it. Chiaki stared at the siren for what felt like hours until Shinobu caught his attention. They were the only two left standing in front of the cage.

"Chiaki…we should go home now. It's getting late." Shinobu said.

"Go home, Shinobu. I'll go home too, don't worry."

Reluctantly, Shinobu left Chiaki alone with the siren in the cage. It was starting to get chilly as the sun set. The siren must be cold. With that thought, Chiaki ran home as quickly as he could and grabbed a pillow and extra blanket in the linens closet. His parents were eating dinner, trying to call him over to eat as well, but he ignored them to run back to the siren.

When he approached it, the siren merely glanced at him before staring off into the ocean again, longing to go back home. Chiaki showed it the pillow.

"Here. Use this." He said, trying to lift the siren's head to place the pillow under. The siren reacted badly, jerking its body away. It scared Chiaki a bit, but he allowed it to settle down before he tried again.

"It's okay. I'm not trying to hurt you. I figured you'd be more comfortable if you had something soft."

He carefully lifted the siren's head again and placed the pillow under it as quickly but gently as he could. The siren seemed surprised at first, but settled down into the soft pillow. Chiaki smiled seeing it at least a little comfortable. He put the blanket in the cage as well, putting it around the siren's body.

"You're probably used to the cold but I think this will make it more comfortable." Chiaki explained himself. He sat quietly with the siren for awhile.

The siren didn't look at him, simply staring off into the distance.

"You know," Chiaki started, sitting himself properly in front of the cage, "I was always told sirens are dangerous monsters who must be killed so we don't lose more sailors in the Siren's Pass. I always believed it. But seeing you being treated like that today…I can't help but feel bad. You probably killed a lot of our residents but I still feel bad. Do you think that's silly?"

The siren didn't respond, not even with another glance. Chiaki didn't expect anything. Its mouth was covered after all. Besides, could sirens even speak? They can sing, for sure, but Chiaki never read anything about sirens talking.

"You're a boy, right?" Chiaki asked. "Your body looks like a human male body. Are there more sirens? Are you a child siren?"

The siren only blinked, continuing to space out.

"Do you have parents? Do you want to go home?"

Something about those questions caused the siren to tear up again. He really was just a child, kidnapped from his home, taken away from his family and locked up like an animal. Sirens are enemies of humankind. According to the books, sirens kill and eat humans. And yet, freeing the siren was the only thing on Chiaki's mind. He didn't deserve any of this.

"The town will hate me for this, but what if I could return you to your home?" Chiaki asked. That elicited a response from the siren. He lifted his head up to look at Chiaki.

"You have to promise me that you won't do your horrifying screech when I take off the duct tape though." He laughed loudly. He covered his mouth, looking around warily. Chiaki tended to be loud without realizing.

Looking back at the siren, Chiaki got approval from him that he won't emit his powerful siren screech. There was no real way to tell if he was lying just to escape, but that won't stop Chiaki from being the hero that he was destined to be. Reaching out a hand, Chiaki took hold of what would be its hands. The siren closed its talons across Chiaki's hand, in an attempt to hold onto it.

There was a feeling of mutual trust for now. Chiaki hoped that it will continue until tomorrow when he will steal the siren from the town and sail it back to the Siren's Pass.


	2. Siren's Pass

**Summary for the Chapter:**

> Chiaki's venture into the Siren's Pass.

**Notes for the Chapter:**

> I've updated the notes on chapter 1, but I'll say it here too. I've changed the anatomy of the sirens to appear androgynous, most of them have flat chests. Arashi will still be referred to as a female siren.

After a short, restless night, Chiaki made his way back into the town square to free the siren. The sun had not risen yet, which meant the townsfolk were still sound asleep. To his surprise, his friends were gathered there too.

"What are you guys doing here?"

"We're here to help, obviously. You think we're going to let you do this alone?" Tetora asked. He pointed to the hoard of tools that he brought from home.

Midori yawned loudly, scratching the back of his head. "I really don't want to, but Kanata dragged me into it somehow..."

As quietly as possible, they used as many tools as they could to break the lock. While Chiaki, Tetora, and Kanata worked on breaking the lock, Midori and Shinobu attempted to untie the ropes binding the siren.

"Duct tape on his mouth is just cruel," Shinobu frowned. He tried to peel the duct tape off carefully, but its strong grip on the siren's skin looked as though it would do damage. "Sorry siren, this might hurt. Please don't scream and make my ears bleed."

"Maybe we should remove the duct tape later," Midori suggested. "If we take it off, can you just fly home?"

The siren shook his head. By the look of his wings, he was still young enough that he could not fly, or could not fly for too long. Given how far the Siren's Pass already was from Ryusei Island, Chiaki would be forced to sail him back home.

Shinobu pat the siren's head. "Wow... soft hair..."

"Got it," Tetora stated as he opened the cage. The lock fell to the floor with a loud clink. Tetora seemed proud of himself.

"So strong," Kanata said.

With the siren free from his cage and the ropes, Chiaki grabbed its talon, pulling it toward the docks. "We don't have much time left. We have to go now before the early birds wake up."

Tetora grabbed his box of tools, immediately following Chiaki and the siren to the docks. The others followed as well, stopping near his small sailboat. Once the siren was on deck, Chiaki stopped his friends.

"I'm sorry, but I don't want to risk anyone's safety. I'll take him home alone," he declared, much to his friends' disappointment. Well, Midori seemed okay with it.

Kanata on the other hand had to speak up. "But Chiaki..."

Chiaki shook his head. "I'm happy you guys helped me free him, but I can't bare the idea of bringing you guys into the dangerous Siren's Pass."

He could tell his friends wanted to argue back, to get him to agree to bring them along, but very few people have returned from venturing into the Siren's Pass trying to find a siren.

"I'll find my way back. I always do!" Chiaki ensured them, tapping his chest with his fist. He flashed a huge grin, his trademark smile when he wanted to spread his positive vibe. It helped ease the tension amongst his friends.

"We'll come find you if you don't come back," Kanata said.

Tetora only gave him a nod, "Have a safe trip."

He noticed how quiet the younger three were, mainly Midori. Chiaki didn't want to press them further about it. He got himself into his boat with a small supplies box. After raising the anchor and sail, Chiaki waved back at his friends.

They continued to watch him until he was but a speck in the dark. There was no turning back now. Setting the boat's course straight toward the Siren's Pass, Chiaki gestured for the siren to approach him.

"Let me try to get the tape off your mouth now," Chiaki said, rummaging through his supplies box. There was a bottle of rubbing alcohol that may help.

"The type of tape they used can harm your skin, so this might hurt. I'm sorry for hurting you in advance. This rubbing alcohol might burn your skin a bit."

With a water bottle ready, Chiaki gently patted the edges of the duct tape with the rubbing alcohol. He let it soak in for a bit before attempting to rip it off slowly. The siren struggled under his grasp, clawing at his arm. It hurt, but he understood the siren was in pain.

The duct tape was starting to peel away, its adhesive residue still on the skin of the siren's face. He poured more alcohol on the corners of the tape that was still stuck.

"Try not to let the alcohol get in your mouth. It's not consumable," Chiaki instructed the siren, tugging at the duct tape a second time.

With part of the siren's lips free, his struggle was becoming more apparent. His voice was able to come out partially as he struggled with the tape's painful adhesive.

"Close your mouth again. I'm going to try to get it off your mouth."

The siren did as he was told, finally sitting quietly. Chiaki poured more alcohol on the tape, trying to rub it between the tape and the siren's skin. While he waited for the alcohol to help ease the adhesive, he poured some water on the siren's mouth that wasn't covered by tape. If he struggled again, he may accidentally taste the rubbing alcohol.

Peeling the tape away, Chiaki managed to free the siren's mouth, but the tape was still on his cheek. The siren let out a big breath of air from his mouth.

"You okay?" Chiaki asked.

The siren nodded. "I'm okay. Thank you."

"You have a name? It'd be rude to not call you by your given name," Chiaki said, grabbing the alcohol to start pulling the rest of the tape off.

"Tsukasa," the siren answered.

"Well, hello Tsukasa. I'm Chiaki of Ryusei Island," Chiaki greeted himself before starting his process again. Tsukasa sat still, obediently waiting for Chiaki to pull off the rest of the tape.

"It hurts."

"I know. It was cruel of them to use this kind of tape on you. It shouldn't be used on skin," Chiaki explained. He started to pull the tape, with Tsukasa responding with his talons digging into Chiaki's arm.

Because he managed to get the duct tape off only a few hours after it had been placed, Tsukasa merely escaped with just skin irritation. If he had waited longer, the duct tape would surely rip his skin off.

"So, do you know which way it is to your home?" Chiaki asked. "I only know the Siren's Pass as a path to a bigger island."

Tsukasa looked out ahead of the boat. "When you pass the entrance to what you humans call the Siren's Pass, you turn right into that large rock that makes it look like a cave. It's not a cave. It's a tunnel."

Chiaki always knew that to be a dead-end cave. Perhaps Ryusei Island needed new history and geography books. While trying to keep the boat on its proper path, Chiaki wrote down details of his journey. He stared at Tsukasa, who was staring in the direction of his home, or so he assumed.

"So there are male sirens too?" Chiaki asked. "I thought sirens were just women."

"My family told me that our group of sirens were banished to this area because we are male sirens," Tsukasa explained. He stared off into the distance. "They wanted to keep the human myth of female-only sirens alive so we were moved here, where they thought there were no humans around. Clearly, they were wrong."

Nodding his head in understanding, Chiaki continued to write down the information given to him. Tsukasa was a knowledgeable child siren. He could write a new siren book for Ryusei Island just by speaking with Tsukasa.

The tunnel entrance itself was already dark. Lowering the sail, Chiaki allowed the boat to glide into the darkness of the tunnel. He began to wonder if sailors got lost in the there, or crashed their boats into the walls when they continued to sail into it without lowering the sails. Although the tunnel was pitch black inside, Chiaki could feel how big it truly was. A true hero should never fear the dark, Chiaki told himself in his mind to ease his fight-or-flight feeling.

"Tsukasa," Chiaki's voice echoed, "Is this how humans have died? They travel in here and their boats crash into the walls. It's too dark to navigate."

"Don't worry. Since we slowed down, your boat can't possibly sustain enough damage to sink. The water is still enough that your boat is not going at a fast enough speed for that to happen."

Even with Tsukasa's words, Chiaki felt uneasy. The prejudices against sirens that he'd learned over the years was that sirens were not to be trusted. They lure humans with temptation, and right now Chiaki had the temptation of knowledge. He was curious about the sirens. He wanted to see more of them.

The boat bumped into the wall, slowly grinding against it as it tried to move in the still water. Chiaki steered the rudder to the opposite direction of the wall. Chiaki's eyes were beginning to adjust to the darkness, although it was still hard to see the water clearly. Tsukasa was moving around, possibly due to anticipation.

"Apparently our singing enchants humans," Tsukasa said.

"Yes. Allegedly," Chiaki added.

"You may want to cover your ears then."

Chiaki rummaged through his supplies box in an attempt to find his earplugs. No good sailor would ever be caught without them around these parts. He plugged his ears as quickly as he could, covering his ears for good measure. The sound was faint, but Chiaki could tell Tsukasa was singing a song.

In the distance, there was some light. They were close to the end of the tunnel. Chiaki steered his boat toward the light. It was silly of Chiaki to think the danger was over just because they managed to escape the tunnel mostly unscathed. The real danger was what was up ahead. Sharp rocks poke out around the exit of the tunnel. Chiaki would have to navigate through them in the darkness of the early morning.

As Chiaki was busy trying to make sense of the water in front of them, Tsukasa jumped up excitedly from something in the clear sky. It looked to be seagulls at first glance so he elected to ignore it to focus on more pressing matters. The boat hit several jagged rocks already, worrying Chiaki.

Tsukasa was waving his wings frantically while staring at him. Chiaki pulled an earplug out, assuming Tsukasa was done singing his song.

"What was that?" Chiaki asked.

"Watch out, Chiaki!"

That was the last thing he heard before he blacked out.


	3. The Queen of Siren's Rock

**Summary for the Chapter:**

> Tsukasa reunites with his family of sirens.

**Notes for the Chapter:**

> (Marge Simpson hiding her face meme) I apologize in advance to KnightsP who read this because I do not know the characters that well which is why I wasted so much time not posting this.

A sharp pain at the back of his head woke Chiaki up. He wasn't sure when he passed out, but the sun was already above the horizon. He winced from the pain as he struggled to sit up. Blinking a few times to get his eyes to adjust, Chiaki took a look around. He was still on his boat, though the boat was jammed between two large jagged rocks. There was a small rock path between the rocks that led to what appeared to be a small mountain.

"Is…this the Siren's Rock?" Chiaki asked himself. He rubbed the back of his head, where he felt a bump.

"Chiaki!"

Tsukasa's distant voice came from somewhere on the rock.

"Tsukasa?"

The morning sun made the ocean water glisten brightly. It made it difficult to see in front of him. Chiaki could hear Tsukasa calling him again. Instead of a friendly face, Chiaki saw a taller siren, about his height, approach him. The first thing he thought upon seeing her clearly was that she was beautiful…until she whacked him over the head with her powerful wing. He stumbled backwards, falling on his butt.

"Leave. Don't come back here," She said threateningly.

"Hey now…" Chiaki started. He noticed Tsukasa flying toward the boat from the Siren's Rock.

"No, wait!" He cried frantically, flapping his little wings as fast as he could.

Tsukasa stumbled into the boat, still adjusting to flying with little wings. He made his way between the female siren and Chiaki, expanding his wings to defend him.

"He's good, I swear. He saved me when no one else wanted to."

The female siren had a fierce expression that never faded away, even with Tsukasa defending a human against her. She went silent for awhile. "How do you know he won't just tell his fellow humans where we live so they can kill the rest of us?"

Tsukasa gulped, not having a real answer to that. Chiaki looked over Tsukasa's wings to face the female siren.

"I would never do that. I risked my life and reputation on Ryusei Island to bring Tsukasa back." Chiaki explained.

"He even came alone, even though his friends didn't want him to," Tsukasa added, "If he had ill intentions, he would have brought them too, wouldn't he?"

After a tense staring contest, the female siren finally moved away from them. Tsukasa let out a small sigh of relief.

"Leave now. We don't want humans here." She said without looking back. She flapped her wings, flying away from the boat.

Tsukasa only offered Chiaki a nervous smile. "Sorry about my big sister. Well, she's not really my sister, but I call her that…Anyway, she doesn't really trust humans."

"It's fine," Chiaki shrugged it off, "I had my own misconceptions about sirens too."

"Thanks for bringing me back home."

"It was my pleasure." Chiaki grinned.

Chiaki realized he hadn't taken off the rest of the tape residue still on Tsukasa's face. Grabbing the alcohol and water bottle, along with a clean rag, he motioned Tsukasa to him. "You still have some tape residue on your face. Let me clean the rest of it off for you before I go."

As Chiaki rubbed the residue off his face, Tsukasa gazed into his eyes. Chiaki curiously took notice of it.

"Will we see each other again?" Tsukasa asked.

"I'm not sure if I'm allowed back here with how your big sister reacted." Chiaki laughed playfully.

Tsukasa shook his head. "Maybe we can visit you on your island."

"That's dangerous. The townsfolk might see you."

After rubbing off as much residue off with alcohol, Chiaki poured water onto the rag to brush the rest of it off Tsukasa's face. "There. That should do it. Go on home now."

Although Tsukasa was grateful at first, he frowned at the inevitable farewell. He grabbed at Chiaki's arm with his talons, pulling him toward the Siren's Rock.

"At least come play with us. We never have guests. When we do it's just enchanted sailors." Tsukasa begged him.

Chiaki shook his head. He could see other sirens peeking out from behind the Siren's Rock. The looming threat of being killed and possibly eaten by a group of sirens was a terrifying thought. As much as he wanted to learn about the sirens from Tsukasa, Chiaki could read the mood around them. He was an unwanted guest.

"Oh, I have something for you." Chiaki said, reaching into a compartment to grab something. It was his sailing hat he wore when his parents took him out sailing. The hat didn't fit as well as it did when he was younger, so he had no use for it anymore.

"This is the hat my parents gave me when I was younger. I have fond memories of wearing this hat all the time when I was sailing with them." He explained, placing the hat on Tsukasa's head.

"Take care of it for me."

In the corner of the boat, the sister siren was listening but refused to look at Chiaki. He understood her resentment, so he won't push anything further than it had to go. He nudged Tsukasa toward his sister, heading back to attempt to dislodge his boat from the rocks. If the damage was not too bad, he could make it back home.

He could hear the flapping of wings as Tsukasa and his sister left his boat. It rocked the boat enough for him to try to nudge the boat away from the rocks.

Watching Chiaki struggle made Tsukasa upset. He was powerless to help since he was still young and not as powerful as the rest of his family. He never turned away from watching his human friend until Chiaki managed to go back through the dark tunnel, swallowed by the darkness.

"Arashi," Tsukasa finally spoke up, "Why'd you scare him away?"

"Humans can't be trusted." His sister answered.

He could hear the flapping of wings from his other family members. They were surrounding him, all taking turns hugging him or making sure he wasn't hurt.

"Tsukasa, I thought you were a goner!" Leo cried, hugging him tightly.

Ritsu yawned, grabbing the hat Chiaki gave to Tsukasa. "Why would you need this old thing? It's useless."

Tsukasa grabbed the hat back, holding it close. "He's my first human friend. It gets a little boring being on this rock with just us here, doesn't it?"

Arashi still seemed angry for whatever reason. Tsukasa was home safe, she should be happy by now especially with Chiaki gone. She muttered something to Izumi before he had a chance to speak to Tsukasa. He nodded before pinching Tsukasa's cheeks, resulting in Tsukasa making a flustered noise.

"Don't go getting kidnapped by humans again, you hear me?" Izumi warned him before flying off with Arashi.

"Where are you two going? Tsukasa just came back home!" Leo called out, but they didn't answer.

"That's the self-proclaimed queen of the Siren's Rock for you," Ritsu shrugged, flying off to his napping spot again. Leo led Tsukasa back up to their sleeping area as well. Up on the highest point of Siren's Rock, where the view of the expansive ocean was unbeatable, Tsukasa looked into the distance, hoping his human friend returned home unscathed.

Tsukasa hadn't realized until then how exhausted he was after his kidnapping and escape.

"I know you've had a long night, so I won't press you about what happened," Leo said, "I'll just let you rest for now. We can talk later."

Tucking the sailor's hat under his head as a makeshift pillow just like the humans used, Tsukasa drifted off to sleep in short time.


	4. Absolute One-Way Street

**Summary for the Chapter:**

> Arashi attempts to help Chiaki travel home safely.

**Notes for the Chapter:**

> Sorry for the slow updates. Again, struggling to write Knights...and I was working on rarepair week. Still not sure how this is going to end but we'll see!
> 
> Also, sorry for going back to quizilla days and adding lyrics to the fic. It's kind of awkward typing that Arashi is singing and not actually putting lyrics in. The song is a Touhou fan song called Once More, Here Again ~ Absolute One-Way Street. I thought it sort of fit the scenario so!

"Hey, why did you tell me to come with you?" Izumi asked.

Arashi stayed silent. She wanted to answer truthfully, but she knew Izumi would tease her about it. It wasn't like she cared about the human. It only seemed fair to make sure he had a safe voyage back home since he returned Tsukasa home. It didn't matter how she worded her reasons, Izumi would find a way to irritate her about it.

There were plenty of jagged rocks sticking out of the water, where the two carefully landed. The two sirens flew to the exit of the tunnel, awaiting the boat to appear. The tunnel was long, so Chiaki could not have made it yet, especially if he were travelling at slow speeds to not damage the boat further.

"Didn't think you would care about a boring human." Izumi commented, obviously bored waiting for him. The comment was likely also a jab at Arashi since she had been so adamant about her stance on humans.

Arashi shot him a glare. "I don't. If he brought Tsukasa back to us safely, the least we can do is make sure he gets home alive."

"And what if he brings back his human colony to kill us?"

"Then we'll kill them." She answered quickly. Arashi had no real interest in killing humans, but they will do it if the humans were threatening them. From their previous experience with humans, they were easy to kill. Most of them were weak without their human-made weapons.

Izumi never changed his tone as he spoke. "Even that idiot on the boat?"

Arashi remained quiet once again. She silently thanked the distant shouts in the tunnel for grabbing their attention. The noise was faint, but she could make out Chiaki's yelling. He could be in trouble. Leaping off the safety of the rock, Arashi flew into the tunnel, her eyes adjusting to the darkness quickly. In the distance were bats flying around here and there. Chiaki was swatting around at the air desperately.

"S-Stay away from me! I'm a powerful hero!" Chiaki threatened weakly, cowering when a bat flew near his head. He ducked down in his boat, on the verge of tears.

_Hero_? The man was afraid of the dark and everything that resided in it. Arashi almost laughed at his fake bravery. She noticed his boat bumping into the dark walls of the tunnel, further damaging his boat. She was not familiar with human boats and how they were built, but it couldn't possibly take more damage than it already had.

Chiaki tried to change the direction of the boat, but the bats flying around were scaring him too much for his boat to leave the walls. The boat bumped into a large rock, knocking Chiaki forward.

Arashi flew around the bats, trying to get them away from Chiaki. Unfortunately, the sound and wind coming from Arashi's wings made Chiaki more frightful. She heard a loud whimper come from him as his boat grind against the rock it got stuck on. The siren wedged herself between the boat and the rock, pushing it away.

"Izumi, a little help please?" Arashi called out.

"You said I had to follow you, not help you." Izumi groaned, but decided to help her anyway.

"W-Who said that?" Chiaki cried from the floor of the boat.

Where was the bravery he had when he brought Tsukasa home? Arashi put the thought in the back-burner for now. She could hear Izumi flying overhead.

"Calm down, will you?" Izumi ordered him, "We're helping you."

With the boat free from its place, Arashi watched the boat make its way toward the end of the tunnel. Chiaki seemed to have calmed down a bit, though he was still shivering. He might know the severity of the damage if he could get close enough to the light.

Arashi was ready to leave when she realized Chiaki could make it back now that the boat was free, but Chiaki screeched once again when water lapped into the boat.

"Oh no, oh no! No, I haven't even left yet!"

She cursed under her breath, wondering what she should do next. If water was getting in, his boat was on the verge of sinking. Izumi only stared at her for what to do next, since he wasn't exactly enticed to help Chiaki in the first place. Arashi flew toward the boat, tugging at whatever her claws could grasp on to, pulling it back toward the Siren's Rock. "Izumi!"

"Yeah, yeah! I'm coming!" Izumi groaned, helping pull Chiaki's boat back home. It was a terrible idea since he would likely starve and die there, but leaving him on a random jagged rock in the middle of the ocean wasn't a better option.

"W-Who's there?" Chiaki whimpered, cowering back in the boat when he noticed it moving away from the Siren's Pass exit.

The boat itself was too heavy for Arashi and Izumi to tug along when it was taking in water. Chiaki splashed about in his boat as he panicked, trying to figure out how he'd survive.

"We have to carry him," Arashi said, flying straight back to Chiaki. She grasped at his arms with her talons, resulting in him freaking out. "Please let us save you! Stop panicking!"

Chiaki's fear made him wriggle enough that Arashi's grip on him slipped. Chiaki stumbled, slipping on his wet boat and falling out. Arashi began panicking when she heard a loud thump right before Chiaki fell into the water.

"Chiaki!"

"And this is why humans die so easily. They freak out over everything." Izumi said bluntly, casually flapping his wings. When Chiaki didn't emerge from the water, Arashi dove in, using her talons to feel around for him in the water. She didn't want to be the one to tell Tsukasa that his first human friend died because she couldn't save him. Izumi sensed her fears, helping her pull him out from the water. Unfortunately he had been knocked out, most likely from slipping and hitting his head on the boat. He managed to grasp at his legs while Arashi grabbed at his arms. The fact that Chiaki and Arashi are both soaking wet now made it much harder to carry the human due to the water weight. Arashi was strong though. She knew she had the strength to get him back to safety. His boat met its unfortunate demise, slowly sinking into the water beneath them. Izumi led the way toward the Siren's Rock, Arashi flying as fast as she could to ensure all of their safety.

When they were just above the Siren's Rock, near one of the cave entrances where they slept, Arashi almost made a crash landing from how exhausted she was. Hopefully that didn't further damage the human's head. Leo heard them flying in, waking up from his nap with Tsukasa. He flew down from his own cave, poking at Chiaki's cheeks.

"Hey, why'd you bring the human back?" Leo asked, studying Chiaki's unconscious body. 

Izumi huffed loudly, still tired from the rescue mission. "Ask her. I'm never doing that for a human ever again."

Arashi sat up, panting. She didn't want to face Leo. Would he be upset with her for it? Leo didn't say anything, but she could tell he wasn't angry. He merely studied Chiaki a bit longer before hitting him on the chest with his talons. Arashi shot him a glare, making him realize he should probably stop messing with the human's body. She moved toward Chiaki, now gazing over his figure as well. 

"Now that I look at him closely," Arashi giggled, "Chiaki's kind of a cute human, isn't he?"

"Looks like a regular, boring human to me. Why can't we just kill him and get on with our lives?" Izumi shrugged, flying off to his resting area near Tsukasa. Tsukasa had woken up from the commotion and peaked out from above, slowly making his way down. He clumsily stumbled on a few rocks, but managed to get down unscathed. Leo on the other hand flew back, most likely to check on Izumi. He had no reason to worry about an unconscious human on their turf.

"Why is Chiaki back?" Tsukasa asked excitedly.

"His boat sank," Arashi answered. She could feel Chiaki's body moving as his small breaths became rhythmic. If a human could have a hypnotic appearance, Chiaki sure had it. He would make a great siren. Shaking her thoughts away from her head, Arashi began to sing. She wasn't sure if it would affect Chiaki if he were sleeping, but she felt the urge to sing something.

"When you were a child, feeling on top of the world,

You came across a small fork in the road and decided to have a little adventure,

Do you remember?"

Tsukasa sat right by her side, closing his eyes to enjoy the beautiful voice coming from Arashi. Her singing may lure humans, but it was like a lullaby to Tsukasa. He loved it when his sister sang.

"At first you were full of excitement, but eventually that energy began to die down,

And in the end, you got lost…

Do you remember how you stood there,

Just how lonely and helpless you felt?"

Deep in the back of her mind, Arashi had a fleeting thought. She told herself that she was singing to entrap Chiaki for herself. Stupid thoughts were normal to have, especially rapid fire ones. Arashi ignored it.

"Every time you see an open seam,

Remember somewhere in your heart,

Just how unreasonable the world can truly be,

Don't look,

Don't come near,

Don't know,

Don't cross over,

Don't bring your footsteps any closer,"

Chiaki stirred around, his eyes fluttering slowly. Arashi gently caressed his face, lulling him back to sleep. Tsukasa began harmonizing with her, singing along softly.

"Don't listen,

Don't come close,

Don't comprehend,

Don't search,

Is there really anything here worth obtaining?

You won't realize until you've completely changed,

Just how impossible it is to turn back..."

"Arashi, do you think humans can get enchanted when they're sleeping?" Tsukasa asked, poking at Chiaki's head.

Arashi stopped singing, turning to face her baby brother. "I'm not sure."

She hoped so.


	5. Survive

**Notes for the Chapter:**

> I don't have anyone who can help me proofread or help me learn how to write Knights properly, so please forgive me if there are mistakes in writing or characterization. I tend to proofread myself but we all know how that usually goes.
> 
> Still no plan for how this fic will end.

When Chiaki opened his eyes, he could only see the red afterglow of the sun setting in the distance. He somehow ended up in a cave, but he couldn't see the ocean. Heading toward the entrance, Chiaki almost walked off the edge of the cliff. Stumbling backwards, Chiaki fell on his butt, his heart racing from the sudden fight-or-flight activation. A noise coming from inside the cave drew his attention away from the cliff.

"Chiaki!" Tsukasa cried, running straight toward him.

"Tsukasa? Where am I?"

"You're at my home!"

The back of Chiaki's head hurt yet again, just like the last time he was at the Siren's Rock. When he rubbed the back of his head there was a bump indicating the injury that knocked him out cold. He flinched from the jolt of pain, but tried not to let it worry him too much.

"My boat!" Chiaki cried, running toward the cliff's edge again. Tsukasa followed right behind him, trying to tug him back inside.

"Chiaki, no! We're really high up and I know humans can't fly. Your boat sank, my sister Arashi said so…" Tsukasa explained to him. Chiaki felt hopeless thinking about his family's boat sinking. It was technically his, but his parents gave him that boat. It held too many memories and important equipment. A few tears threatened to fall from his eyes, but he refused to cry in front of anyone, especially Tsukasa.

Swallowing his nervousness, Chiaki offered a smile that looked more worried than happy. "Guess I'm stuck here then, huh?"

"It's okay. We can feed you!" Tsukasa pointed at a fresh fish pile sitting in a small corner of the cave. Given that the fish were still gasping for water and flopping around, Chiaki guessed they were recently fished out of the ocean.

"Thanks, but humans need to cook food before eating it, and I don't have any source of water to survive longer than three days," Chiaki said, suddenly anxious about his own inevitable demise.

Tsukasa shook his head. "We have a water source at the very top of this rock. Also, what's a cook?"

"Cooking is when you put food over a fire to let it burn slowly. Humans need to consume food in a very specific way."

"Wow, you can't just eat the fish out of the water?"

"No," Chiaki chuckled. Seeing the young siren's eyes light up from all the new knowledge was adorable.

"How do I get a fire?"

"I have to make it with some sticks or wood," Chiaki said, looking around outside to see if there was anything that was flammable. There was nothing but the rocks and the sand below him.

"I'll ask my brother to get some for you," Tsukasa offered him as he made his way to a lower cave entrance. Chiaki sighed, sitting down at the ledge, overlooking the large looming cave in front of him known as the Siren's Pass. Despite being happy to be able to see the sirens again, namely Tsukasa, Chiaki felt doomed. Of course, he'd never let that show in front of the child siren. Deep down, he knew his fate on Siren's Rock. Just like the humans who previously landed here, Chiaki would meet his inevitable demise.

The worst part of it was that he'd be alone. He missed his parents. He missed his friends. He missed being home. He missed his books, sitting idly on his bookshelves in his room, waiting to be read. The things in his boat were gone too, in the bottom of the ocean somewhere in that cave. He had nothing left but to die just like the other sailors who dared to come to Siren's Rock.

"I thought you were a hero," Arashi's voice startled him, causing him to turn around to see her walking toward him from deep inside the cave. She didn't look angry like last time, but cautious. Chiaki wiped his eyes, only just realizing he may have shed a tear or two thinking about home.

"O-Of course I am!" Chiaki laughed anxiously, turning his head away from the siren. He could hear her approach him, talons scraping against rock as she walked closer. He didn't want her to see him like that. He had a façade to put on if he were going to die surrounded by the sirens. That, or if they choose to kill him first.

Arashi sat next to him, placing her head against his chest. Chiaki blushed, stumbling backwards. "W-What are you doing?"

"I can hear your heartbeat, you know," Arashi commented, unsure why he was so frantic. "You seem really upset about something. Scared you'll die here just like your other human friends?"

Chiaki's nervous curiosity turned into the sadness Arashi could feel radiating from him. He looked down at his hands in defeat, unsure of himself now. No matter how he twisted the scenario, there was no way he would make it out alive. Even if his parents and friends came to look for him, they would most likely perish as well.

Arashi almost felt bad for asking him so bluntly. Seeing the happy-go-lucky human so upset was different to her. She tilted her head sideways out of curiosity when Chiaki began to tear up. Okay, now she really felt bad.

"I'm happy I get to spend time with Tsukasa here, but I know in the end, I may just die here…" Chiaki said, wiping at his eyes. "I don't want to, but I don't see any way of surviving here. I miss my parents, my friends, my island, I miss them all already. I don't want to die alone."

It was then that Arashi felt empathy. She knew the feeling of not wanting to live and die alone with no one to be there with her in her final moments of life. Due to her current siren family being kicked off the larger siren colony's island, Arashi left on her own, following them to this rock. She would never abandon her friends or family, and she'd never let them feel alone. Now, a human was on this rock with them, but he felt alone. Arashi could only feel empathetic to his plight.

She flapped her wings to get herself up from the ground. "I'll get you your fire."

"Wait, Arashi," Chiaki called out to her, a hand extended out.

"Yes?"

"Thank you, for helping a human like me," Chiaki smiled, though it still seemed melancholic. His soft smile made Arashi feel flustered. She pouted a bit at the reaction, flying off into the distance to get Chiaki whatever he needed to survive.

Chiaki watched her fly away, admiring the beauty of the siren. If he only had a notebook to write and draw the things he had learned about sirens, perhaps his legacy could live on as the man who lived amongst the sirens. He wondered where the nearest island was from the Siren's Rock that was inhabited by humans. He'd hate for the sirens to do all the work for him, but it'd be nice to have some form of human creation with him on the island.

He sat inside the cave now, hugging his knees to his chest as he thought back to his family again. He hid his head in his arms, sighing loudly at the thought of never seeing them again. While Chiaki was deep in thought, there was another flap of wings coming into the cave. The wind from the wings blew at his hair, but Chiaki didn't budge.

"Hey, human."

Chiaki peaked up slowly, his sad eyes trying to hide his true feelings again though to no avail. The siren had fluffy, silver hair, his face stoic. He didn't respond, prompting the siren to speak again.

"Tsukasa asked me to bring you a fire? Mind telling me what that is and why I should bother helping you?"

"You don't have to help me. Sorry for troubling you," Chiaki apologized, putting his head back in his arms. He didn't want to be bothered at the moment.

There was another flap of wings coming in, though it sounded smaller. Chiaki immediately stood up, his entire demeanor changed when he saw Tsukasa flying in happily. "Izumi!"

The siren called Izumi noticed Chiaki's sudden change when Tsukasa appeared, but said nothing to him about it. He squeezed Tsukasa's face, chuckling to himself when Tsukasa jerked back angrily.

"Stop that! Not in front of our guest!" Tsukasa pointed at Chiaki. "Let's go get the fire for him, please?"

"I'm not going to bring you with me. I'll bring Ritsu instead. He's been sleeping all day, he needs to stretch his wings," Izumi said, patting his head gently.

"Don't worry about the firewood. Arashi is currently on her way to get that," Chiaki said.

Tsukasa nodded, looking at Izumi. "Can you get something else for Chiaki too then?"

"I guess," Izumi sighed, letting it be known he really didn't want to help the human. Chiaki noticed how Izumi didn't want to help in the first place, assuming he only wanted to help Tsukasa feel better.

"Do you need anything else, Chiaki?"

"You guys are already doing so much for me, I don't want to burden you guys further," Chiaki waved a hand, trying to dismiss their offer.

"It would be shameful for us hosts to not cater to our guest," Tsukasa boasted, possibly trying to imitate an adult siren. Izumi rolled his eyes, though he was kind of smiling at the same time Chiaki noticed.

"If you can find anything that looks like a human created it, that'd be nice. I kind of miss having a notebook and pen, and books and…" Chiaki stopped himself, not trying to seem spoiled, "I just need something that can hold water, just so I can carry it with me."

"I'll see what I can find," Izumi said in response. He flew off to another cave entrance to recruit the siren Chiaki assumed to be Ritsu, the two flying off toward the setting sun.

The small moment of hopelessness he had was already a distant memory to Chiaki. How could he be a hero if he gave up so soon? A new flame within his heart burned. He smiled hopefully as he looked into the distance, watching the specks in the sky that is Izumi and Ritsu flying off to find him whatever he needed. Chiaki was eternally grateful for the sirens. They were helping him even though they could have just killed him or let him drown whenever his boat sank. He will get through it. He believed it. He hoped.

The only thing Chiaki could do was wait in hopes of the sirens finding some wood to burn so he doesn't freeze from the cold, frigid sea air for the incoming night.


End file.
